Impeller for automotive fuel pump

ABSTRACT

An impeller for an automotive fuel pump, designed to minimize energy loss due to collision with fuel at fuel-inflow regions of blade chambers, is disclosed. The impeller includes a disk-shaped impeller body, a plurality of arched main blades radially provided at a peripheral area of the impeller body with arched blade chambers defined therebetween, and a plurality of arched auxiliary blades radially disposed between the main blades. Each of the blade chambers is provided at its inner side with an inner ridge portion defining upper and lower fuel-inflow regions and at its outer side with an outer ridge portion defining upper and lower fuel-outflow regions. The main and auxiliary blades are alternately arranged. The blade chambers are divided into arched sub-chambers by the auxiliary blades. Each of the auxiliary blades has a length shorter than that of each of the main blades and has a sharpened inner end. The sharpened inner end of the auxiliary blade is connected to the inner ridge portion so as to provide upper and lower flow paths separated from each other by the inner ridge portion.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invention relates to an impeller for an automotive fuel pump, and more particularly to an impeller for an automotive fuel pump which is designed to minimize energy loss due to collision with fuel at fuel-inflow regions of blade chambers in the course of supplying fuel to an engine, such as an internal combustion engine, thereby improving pumping efficiency of fuel.

[0003] 2. Description of the Prior Art

[0004] In general, a fuel supply pump, which is equipped in automobiles, is intended to efficiently supply an engine with fuel sucked from a fuel tank.

[0005] Referring to FIG. 1, there is shown a conventional fuel supply pump. As shown in FIG. 1, the fuel pump 100 includes a pump housing 200 having a certain shape, an impeller 300 rotatably received in the pump housing 200, a drive motor 400 for rotating the impeller 300, and a check valve 500 for allowing fuel, sucked by turning force of the impeller 300, to be discharged.

[0006] As shown in FIG. 2, the impeller 300 equipped in the fuel pump is shaped to have a disk form, and includes a plurality of blades 320 radially arranged on a peripheral area of the impeller 300, and a plurality of blade chambers 340 defined between

[0007] A basic principle of supplying fuel by use of the impeller 300 may now be described as follows. That is, as the impeller 300 is rotated in the pump housing 200, fuel received in the chambers 340 is repeatedly circulated in a flow channel 220 formed in the pump housing 200 while exiting one of the chambers 340 along its outer wall and entering the next adjacent chamber 340 along its inner wall, by centrifugal force generated by rotation of the impeller 300.

[0008] However, such a conventional impeller 300 cannot achieve efficient supply of fuel owing to the following reasons. Since the blades 320 are uniformly arranged in a circumferential area of the impeller 300, fuel, which is raised toward inner side of the chambers 340 through the flow channel 220 of the pump housing 200, repeatedly collides with the blades 320, thereby causing energy loss due to the collision, and thus lowering pumping efficiency.

SUMMARY OF THE INVENTION

[0009] Accordingly, the present invention has been made keeping in mind the above problems occurring in the prior art, and an object of the present invention is to provide an impeller for an automotive fuel pump, which is installed in a pump housing to suck and discharge fuel, and which is designed to minimize energy loss due to collision with fuel at an inflow area, thereby improving the pumping efficiency of fuel.

[0010] In order to accomplish the above object, the present invention provides an impeller for an automotive fuel pump, comprising: a disk-shaped impeller body; a plurality of main blades radially provided at a peripheral area of the impeller body with blade chambers defined therebetween; and a plurality of auxiliary blades radially extended from the centers of outer surfaces of the blade chambers without invading inner fuel-inflow regions of the blade chambers, and sharpened at inner ends thereof.

BRIEF DESCRIPTION OF THE DRAWINGS

[0011] The above and other objects, features and advantages of the present invention will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings, in which:

[0012]FIG. 1 is a cross-sectional view of a fuel pump equipped with a conventional impeller;

[0013]FIG. 2 is an enlarged perspective view of the conventional impeller shown in FIG. 1;

[0014]FIG. 3 is a perspective view of an impeller according to the present invention;

[0015]FIG. 4 is an enlarged perspective view of the impeller shown in FIG. 3, which is partially broken away;

[0016]FIG. 5 is a plan view of the impeller shown in FIG. 3;

[0017]FIG. 6 is a cross-sectional view of a fuel pump equipped with the impeller according to the present invention;

[0018]FIG. 7 is an enlarged perspective view of the impeller according to the present invention, which shows functions of the impeller; and

[0019]FIG. 8 is a plan view of an impeller according to another embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

[0020] This invention will be described in further detail by way of example with reference to the accompanying drawings.

[0021]FIG. 3 is a perspective view of an impeller according to the present invention, FIG. 4 is an enlarged cross-sectional view of the impeller shown in FIG. 3, and FIG. 5 is a plan view of the impeller shown in FIG. 3.

[0022] As shown in FIGS. 3 to 5, the impeller 10 according to the present invention is shaped to have a disk form. The impeller is provided at its peripheral area with a plurality of blades defining chambers therebetween.

[0023] The plurality of blades includes main blades 12 and auxiliary blades 14, which are alternately arranged and radially orientated. Each of the auxiliary blades 14 is sized to be ⅓-⅔ of a length of each of the main blades 12.

[0024] Blade chambers 16 are defined between the adjacent main blades 12. Each of the chambers 16 is provided at a lower portion of its inner surface with an arched fuel-inflow region 16 a and, at an upper portion of its inner surface, with an arched fuel-outflow region 16 b, each of which are shaped to be symmetrical to the other.

[0025] The auxiliary blades 14, which are alternately arranged with respect to the main blades 12, are radially and inwardly extended from the centers of the outer surfaces of the blade chambers 16. Each of the auxiliary blades 14 has an inner end, which is formed to have a wedge-shaped section and is coupled to a boundary ridge between the fuel-inflow region 16 a and the fuel-outflow region 16 b, thereby defining an upper flow path 14 a on the boundary ridge and lower flow path 14 a under the boundary ridge.

[0026] Since the. main blades 12 and the auxiliary blades 14 are curvedly extended toward the center of the impeller 10 and have vertical side surfaces, the blade chambers 16 are divided into arched sub-chambers 13 by the auxiliary blades 14 disposed at the center thereof.

[0027] As shown in FIG. 6, the impeller 10 which is constructed in the above-described manner is installed in a pump housing 2 of the fuel pump 1 and is rotated at a high rotational speed by a drive motor 3 so as to suck fuel from a fuel tank and to discharge the fuel to an engine.

[0028] An operation of supplying fuel by the impeller 10 according to the present invention is described in detail, with reference to FIGS. 6 and 7.

[0029] The impeller 10 is received in the pump housing 2 comprised of an upper cylindrical case 22 and a lower cylindrical case 24, and is coupled to a rotating shaft of the drive motor 3 passing through a shaft hole of the upper case 22. Inner surfaces of the upper and lower cases 22 and 24 facing each other are formed with upper and lower annular channels 22 a and 24 a so as to guide flow of fuel. The upper case 22 is provided with an outlet 22 b, and the lower case 24 is provided with an inlet 24 b.

[0030] The impeller 10 is rotatably installed between the upper and lower cases 22 and 24, such that the main and auxiliary blades 12 and 14 of the impeller 10 are aligned with the upper and lower channels 22 a and 24 a formed at the upper and lower cases 22 and 24.

[0031] When the impeller 10 is rotated at a high rotational speed in the pump housing 2 by the drive motor 3, intensive suction force is generated in the upper and lower chambers 22 a and 24 a of the upper and lower cases 22 and 24 disposed on upper and lower surfaces of the impeller 10 by a frictional force, due to rotation of the main blades 12 and the auxiliary blades 14. Consequently, fuel reserved in the fuel tank is sucked in the flow channels 22 a and 24 a through the inlet 22 b formed at the inlet 24 b of the lower case 24, and is discharged through the outlet 22 b of the upper case 22.

[0032] A circulation operation of fuel is now described in detail, with reference to FIGS. 4 to 6.

[0033] When the impeller 10 is rotated while being in close contact with the upper and lower cases 22 and 24, the fuel in the fuel tank is sucked through the inlet 24 b of the lower case 24 by a frictional force due to rotation of the main and auxiliary blades 12 and 14. The fuel sucked through inlet 24 b is raised through the sub-chambers 13 of the blade chambers 16 defined between the main blades 12 and the auxiliary blades 14 while being rotated along the lower flow chamber 24 a.

[0034] The fuel in the sub-chambers 13 is further raised by a centrifugal force of the impeller 10. At this point, the fuel exits from the fuel-outflow areas 16 b disposed at outer portions of the sub-chambers 13, and enters the fuel-inflow areas 16 a disposed at inner portions of the next adjacent sub-chambers 13 through the upper flow chamber 22 a. Accordingly, the fuel is spirally circulated in the blade chambers 16 and the flow chamber 22 a.

[0035] At this point, since the flow paths 14 a are defined between the fuel-inflow areas 16 a provided at inner sides of the blade chambers 16, and at the inner ends of the auxiliary blades 14 which are inwardly extended from the centers of the outer wall of the blade chambers 16, it is possible to minimize energy loss due to fuel, entering the fuel-inflow areas 16 a, coming into collision with the blades. Consequently, fuel can be smoothly circulated and efficiently discharged, and a cavitation phenomenon due to flow separation on the surfaces of the blades can be suppressed.

[0036] Furthermore, since the inner ends of the auxiliary blades 14 have sharp sections, i.e., wedge-shaped sections, fuel can be more smoothly circulated in the chambers.

[0037]FIG. 8 is a plan view of an impeller 10′ according to another embodiment of the present invention.

[0038] As shown in FIG. 8, according to this embodiment, two or more auxiliary blades 14′ are provided between adjacent main blades 12′, so as to minimize energy loss due to collision with fuel.

[0039] As described above, the present invention provides an impeller for an automotive fuel pump, which is installed in a pump housing so as to suck fuel from a fuel tank and to supply the fuel to an internal combustion engine. The impeller is designed to minimize collision between its blades and fuel entering chambers defined between the blades, so that energy loss due to the collision with fuel is decreased, and a discharging efficiency of fuel is increased.

[0040] Although preferred embodiments of the present invention have been described for illustrative purposes, those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims. 

What is claimed is:
 1. An impeller for an automotive fuel pump, comprising: an impeller body shaped to have a disk form; a plurality of arched main blades radially provided at a peripheral area of the impeller body with arched blade chambers defined therebetween, each of the blade chambers being provided at its inner side with an inner ridge portion defining upper and lower fuel-inflow regions and at its outer side with an outer ridge portion defining upper and lower fuel-outflow regions; and a plurality of arched auxiliary blades radially disposed between the main blades and inwardly extended from the centers of outer surfaces of the blade chambers, such that the main and auxiliary blades are alternately arranged and the blade chambers are divided into arched sub-chambers, each of the auxiliary blades having a length shorter than that of each of the main blades and having a sharpened inner end, the sharpened inner end of the auxiliary blade being connected to the inner ridge portion so as to provide upper and lower flow paths separated from each other by the inner ridge portion.
 2. The impeller as set forth in claim 1, wherein at least two auxiliary blades are provided between the two adjacent main blades. 